The invention relates to a circuit arrangement that includes at least a source contact, a gate contact, and a Schottky-Reverse contact, which Schottky-Reverse contact being embodied as a Schottky-contact on a barrier layer of the circuit arrangement and being connected to the source contact such that electrons can flow in a return operation via the Schottky-Reverse contact from a drain contact to the source contact.
Circuit arrangements of the type mentioned at the outset are typically used for power applications, for example for power transistors. Such a power transistor typically comprises a drain contact, a source contact, and a gate contact. The gate contact is arranged on a barrier layer. A passivation is provided between the drain contact and the source contact, which surrounds the gate contact and essentially isolates the three contacts in the blocked state. Below the barrier layer typically a two-dimensional electron gas is embodied in a transistor channel in a forward operation of the power transistor, so that the electrons can flow from the source contact to the drain contact.
In a plurality of power applications, e.g., in semi-bridge and full bridge topologies, a diode behavior is desired between the source contact and the drain contact of a power transistor in order to protect the power transistor from damages by excessive voltages, particularly in the return operation.
From prior art it is known to this regard to generate this diode behavior by a parallel switching of the power transistor with a diode, a so-called return diode.
In the known realizations of prior art with a parallel switching of a diode it is disadvantageous that both the power transistor as well as the parallel switched diode must be realized as separate components. This can be realized either in a monolithic or a hybrid form. In the monolithic realization a lot of space is required and thus a large-scale and cost-intensive component results.
Alternatively, a transistor is known from prior art, in which a Schottky-Reverse contact is arranged between the drain contact and the gate contact. This Schottky-Reverse contact replaces as an integrated return diode the parallel switching of the diode and leads in the return operation to a diode behavior of the arrangement.